from __future__ import absolute_import
"""
    M2Crypto utility routines.

    NOTHING IN THIS MODULE IS GUARANTEED TO BE STABLE, USED ONLY FOR
    INTERNAL PURPOSES OF M2CRYPTO.

    Copyright (c) 1999-2004 Ng Pheng Siong. All rights reserved.

    Portions created by Open Source Applications Foundation (OSAF) are
    Copyright (C) 2004 OSAF. All Rights Reserved.
"""

import binascii
import logging
import sys

from M2Crypto import m2, py27plus, six
if py27plus:
    from typing import Any, AnyStr, Optional, Tuple, Union  # noqa
    # see https://github.com/python/typeshed/issues/222
    AddrType = Union[Tuple[str, int], str]

log = logging.getLogger('util')


class UtilError(Exception):
    pass

m2.util_init(UtilError)


def pkcs5_pad(data, blklen=8):
    # type: (str, int) -> str
    pad = (8 - (len(data) % 8))
    return data + chr(pad) * pad


def pkcs7_pad(data, blklen):
    # type: (str, int) -> str
    if blklen > 255:
        raise ValueError('illegal block size')
    pad = (blklen - (len(data) % blklen))
    return data + chr(pad) * pad


def bin_to_hex(b):
    # type: (bytes) -> str
    return six.ensure_text(binascii.b2a_base64(b)[:-1])


def octx_to_num(x):
    # type: (bytes) -> int
    return int(binascii.hexlify(x), 16)


def genparam_callback(p, n, out=sys.stdout):
    # type: (int, Any, file) -> None
    ch = ['.', '+', '*', '\n']
    out.write(ch[p])
    out.flush()


def quiet_genparam_callback(p, n, out):
    # type: (Any, Any, Any) -> None
    pass


def passphrase_callback(v, prompt1='Enter passphrase:',
                        prompt2='Verify passphrase:'):
    # type: (bool, str, str) -> Optional[str]
    from getpass import getpass
    while 1:
        try:
            p1 = getpass(prompt1)
            if v:
                p2 = getpass(prompt2)
                if p1 == p2:
                    break
            else:
                break
        except KeyboardInterrupt:
            return None
    return p1


def no_passphrase_callback(*args):
    # type: (*Any) -> str
    return ''